The credit crunch has claimed another major casualty the £324m British Seafood Group, which has fallen into administration.

Deloitte was appointed administrator for the company, a fish supplier to manufacturers and the foodservice sector, on 19 February. Its subsidiaries, such as Grimsby fish traders Five Star Fish, are trading as normal, with supply arrangements expected to be discussed shortly.

The company fell into administration after it defaulted on trade credit commitments. Private equity investor 3i confirmed it had already written off its £81m stake in the business. "This is fundamentally a good business, but the tightening of the credit markets have made it increasingly difficult for the business to access trade finance," said a 3i spokeswoman.

Administrator Matt Smith said Deloitte was still exploring the options, including the sale of the business as a going concern. "We are going to lose a lot of money," a creditor said, "as it is unrealistic to claim back the fish we have supplied."

British Seafood had enjoyed several years of strong growth, with sales increasing more than 25% for the sixth consecutive year in its most recently published accounts for the year to 31 December 2008. Turnover was £324m, with operating profit increasing 19% to £26.4m, but net debt had risen to £160m by the year-end.

The company has been listed in The Sunday Times' 150 fastest-growing companies for the past five years, and its owner Mark Holyoake appears at number 1,077 in The Rich List, with £50m.